By the way: Mobac (Mobile Atlas Creator), has a very good code, extremely well organized and readable, and a building process that is "one command away".
So it was next to a breeze to add the option to create the map tiles as "PNG, 16 shades of grey" - which on EPD optimizes (halves) the map file size.

I had not proposed the addition of such option to the author, but that's quickly done.